Display devices for vehicles today can display various kinds of information received from television receivers, audio devices, DVD players, and the likes, as well as navigation information.
A known display device for vehicles outputs different display images directed to the driver's seat and the passenger's seat. For example, navigation information is displayed for the driver, while a television image, a DVD image, or the like is displayed for the passenger in the passenger's seat (see Patent Reference 1, for example).    [Patent Reference 1] Japanese Unexamined Patent Publication No. 2004-206089